1. Field of the Invention
The present invention relates to an electrophotographic photosensitive member and a process for producing the electrophotographic photosensitive member, more particularly to an electrophotographic photosensitive member which has an electroconductive support having been cleaned by a specified method and an interlayer, and a process for making it.
2. Related Background Art
Generally, an electrophotographic photosensitive member comprises an electroconductive support and a photosensitive layer formed thereon. The material useful for the electroconductive support includes metals such as aluminum, copper, iron, brass, and stainless steel, and alloys thereof. Among them, aluminum is most widely used because of its high workability and high dimensional stability. The electroconductive support is usually worked by rolling, casting, machining, or the like. The worked surface of the support,is usually contaminated with oily materials such as working oil, machining oil, and rust preventive oil used during working (kerosene, polybutene, etc.), or shavings of the working, dust in the air, human fingerprint, etc.
If a photosensitive layer is formed on the support having such conditions, the resulting layer cannot be uniform and does not work as a photosensitive member, or even if it works it gives low quality images when used in an electrophotographic apparatus (copying machines, laser beam printers, LED printers, liquid crystal shutter printers, and facsimile machines).
Accordingly, complete cleaning of the support is indispensable in the production of electrophotographic photosensitive members.
Heretofore, supports for electrophotographic photosensitive members are cleaned using a halogenated hydrocarbon such as trichloroethylene, trichloroethane, dichloromethane, and carbon tetrachloride for their degreasing property, non-combustibility, and quick drying property. Acids and alkalis are also known to be useful for cleaning. Further, as a dry cleaning methods, it is known to irradiate with ozone, UV rays, or the like to decompose adhered contaminants.
The organic solvents, however, including the halogenated hydrocarbon solvents, may adversely affect not only human bodies but also the global environment. The use of an acid or an alkali requires a neutralization process, or may cause corrosion of the surface of the support. The ozone itself has harmful effects on human bodies. To avoid the above disadvantages, a large scale installation is necessary, requiring a large installation area and a high cost.
To solve the problems, methods for cleaning a support with water are disclosed in Japanese Laid-Open Patent Application Nos. 58-14841, and 1-130159.
In the cleaning of the support with a liquid mainly composed of water, the degree of cleaning is improved effectively by using an auxiliary agent such as a surfactant, cavitation effect of ultrasonication, high-pressure water jet from a jet nozzle, and additionally by using a brush or a blade.
When the cleaning with water, however, a non-uniform oxide film may be formed on the support surface, or the surface may be toughened, which may affect adversely the characteristics of the electrophotographic photosensitive member.
To meet the recent requirements for higher image quality, higher speed, and higher durability in electrophotography, electrophotographic photosensitive members having more satisfactory properties have been pursued.